This invention relates in general to air conditioning systems and in particular for a system for recovering Freon from non-condensible gases.
In air conditioning systems Freon, a liquid fluorinated hydrocarbon, or a similar refrigerant, is used as a cooling medium. The Freon is expanded to absorb heat from the interior of a building or factory and is condensed or compressed to extract the heat at another location, usually outside the building. It is not uncommon for air and other non-condensible gases to enter the refrigeration cycle at some point. The non-condensible gases collect in the condenser and interfere with the proper operation of the cooling system and must be removed.
In the past, it has been common practice to vent the non-condensible gases to atmosphere. However, the non-condensible gases contain some Freon vapor which is an atmospheric pollutant and may be subject to Environmental Protection Agency (EPA) regulations. Also, in commercial or industrial applications, the amount of Freon vapor vented to the atmosphere results in an unnecessary expense, sometimes a large expense since the Freon lost to atmosphere must be recharged back to the system.
Prior attempts to recover the Freon vented to the atmosphere or separated from the non-condensible gases have not met with great success. One method commonly practiced has been to use the refrigerant from the air conditioning unit to circulate through a purge condenser to condense out the Freon vapor from the non-condensibles. This has met with some problems since the refrigerant temperature fluctuates depending on the load of the air conditioning unit and ambient temperature. Thus the non-condensibles released from the purge condenser still contain some Freon vapor.